Limnogale's curious use of latrine sites provides a golden opportunity for research on its conservation status and biogeography. Despite its elusiveness, documenting its occurrence is remarkably straightfoward thanks to the copious deposits of readily identifiable feces at latrine sites. The use of fecal surveys for assessing Limnogale's status has been championed in the past (Nicoll and Rathbun, 1990; Benstead et al., 2001; Benstead and Olson, in press), but no such study has been undertaken.

We have used GIS data to develop a strategy for conducting fecal surveys of representative sections of all major river systems of central eastern Madagascar (see figure). These sites have been chosen based on road access, proximity to historical sites and protected areas, and consultation with Malagasy colleagues. While this is an ambitious project in geographic scope, our previous experience conducting fecal surveys for Limnogale in and around Ranomafana as well as that of other researchers we have contacted indicates that such an approach is the most rapid and efficient means for documenting Limnogale's occurrence. Working in two teams of two (plus a driver), both sides of targeted streams and rivers will be surveyed on foot in a leapfrog fashion, using 2-way radios to communicate between team members.

Feces will be counted, collected and preserved in sterile 80% ethanol for subsequent DNA extraction and diet analysis (see next section). Density of feces will be expressed as numbers of fecal pellets per square meter of habitat surveyed. Habitat variables to be measured in the survey reach (20-40 x mean width) at each site include mean percent canopy cover, stream slope, mean water velocity, mean channel width and maximum depth, substrate type, percent sediment cover, simple indices of prey community composition, and catchment/riparian vegetation type. Location of each survey site and its elevation will be recorded by a global positioning system. We will rely heavily on local guides to navigate along rivers, assist with interviews, and search for Limnogale latrine sites; our experience has shown the assistance of local guides to be invaluable.

Results of the fecal survey will be used to generate an updated distribution map for Limnogale. Habitat data will be used to build logistic regression models that identify habitat variables that predict the presence of Limnogale, based on the presence/absence of feces (Carroll et al. 1999, Orrock et al. 2000). Numbers of fecal pellets found will also be used with the same data (from the subset of sites where evidence of Limnogale is found) in standard multiple regression models in order to identify variables that are correlated with fecal density (a proxy for Limnogale density). Dietary analysis will be conducted using the methods of Benstead et al. (2001).

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